Rotary-engine.



PATENTED MAR. 7, 1905.

C. W. OARMAN.

ROTARY ENGINE. APPLICATION FILED 00w. 18.1904.

2 SHEETS-SHEET 1.

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Witnesses Inventor No. 784,248. PATENTED MAR. 7, 1905.

G. W. GARMAN.

ROTARY ENGINE.

APPLICATION FILED OUT. 18.1904.

2 SHEETS-SHEET 2.

Witnesse W firww NITED STATES Patented March 7, 1905.

PAT NT FFICE.

CHARLES WV. CARA IAN, OF SARCOXIE, MISSOURI, ASSIGNOR OF ONE-HALF TO IRAE. ADAMS, OF SARCOXIE, MISSOURI.

ROTARY ENGINE.

SPECIFICATION forming part of Letters Patent No. 784,248, dated March'7, 1905. Application filed October 18, 1904. Serial No. 228,967.

To 1/ whom it ntay concern:

Be it known that I, CHARLES W. CARMAN, a citizen of the United States,residing at Sarcoxie, in the county of Jasper and State of 5 Missouri,have invented a new and useful Rotary Engine, of which the following isa specification.

This invention relates to rotary engines, and has for its principalobject to provide a To novel form of engine in which provision is madefor supplying and exhausting the actu ating fluid through the mainshaft, the latter being hollow and forming both an inlet and exhaustpassage, terminating at ports within the cylinder.

A further object of the invention is to providea novel form ofpiston-wing so constructed that dead steam may freely escape from thecylinder in all positions of the wing.

A still further object of the invention is to provide an improved meansfor governing the speed of the engine, and, further, to avoid the dangerof leakage of steam by placing a governor and controlling-valve directlyin the steam-chest.

A still further object of the invention is to provide means whereby thesensitiveness of the governor may be readily adjusted while the engineis running in order to increase or 0 decrease the speed.

\Vith these and other objects in View, as will more fully hereinafterappear, the invention consists in certain novel features of constructionand arrangement of parts hereinafter fully described, illustrated in theaccompanying drawings, and particularly pointed out in the appendedclaims, it being understood that various changes in the form,proportions, size, and minor details of the struc- 40 ture may be madewithout departing from the spirit or sacrificing any of the advantagesof the invention.

In the accompanying drawings, Figure 1 is a transverse sectionalelevation of a rotary v engine constructed in accordance with theinvention. Fig. 2 is a sectional plan view of the same on the line 2 2of Fig. 1, the parts being shown in plan. Fig. 3 is a sectionalelevation of the end portion of the steamehest, showing the means foradjusting the tension of the balance-spring. Fig. I is a transversesectional view of the shaft on the line 4 A of Fig. 2. Fig. 5 is a sideelevation of the annular cut-off valve, showing it in position on thehollow shaft of the engine.

Similar numerals of reference are employed to indicate correspondingparts throughout the several figures of the drawings.

The engine is provided with a suitable base 10, that is preferablyformed'integral with the circular cylinder 11. The heads 12 and 13 ofthe cylinder may be formed of separate members bolted to the cylinderproper, or one of said heads may be formed integral with the cylinder,as shown in Fig. 2. Through both heads extends a shaft 1 1, one end ofsaid shaft being supported in a suitable bearing formed in a support 15,that is carried by the base, while the cylinder-head 13 forms a bearingfor the opposite end of the shaft. The cylinder-head 12 is provided witha suitable stuffing-box 16 in order to prevent leakage of the steam, andbetween the stuffingbox and the bearing 15 a combined balance and beltwheel 17 is mounted on the shaft. The size and character of thebalance-wheel will of course vary with .the horse-power of the engineand the work which it is intended to perform. \Vithin the cylinder is apiston 18, that may be formed integral with the shaft or securedthereto, as desired. The piston and the shaft are hollow and the pistonis divided into two chambers by a transverselydisposed partition 19. Inthe wall of one chamber is a steam-inlet port 20, through which steampasses to the cylinder, and in the opposite chamber is a steam-exhaustport 21., from which the steam passes, the steam exhausting at the outerend of the shaft or being conveyed away by a suitable exhaustpipe. On.the ends of the body of the piston are secured disks 22 of a diameterabout equal to the internal diameter of the cylinder, and these disksare connected by a piston-wing 23, that is carried by a central portionof the piston. The forward face of the piston-wing is arranged on acurved line and forms a cam for successively opening movable abutments24, the abutments being moved outward by the wing and then after thewing has passed being moved inward until their inner edges engage thecylindrical portion of the piston. At the opposite sides of the cylinderare arranged abutment-chambers 25, which may be formed integral with thecylinder-casting, but preferably are formed of separate .casings thatmay be readily detached in order to examine or repair the abutments. Theopposite side walls of the abutment-casings form supports fortransversely-extending pins 26, on which the inner ends of the abutments24 are mounted, the blades of the abutments passing through suitableopenings formed in the wall of the cylinder and packing-strips 28 beingused in order to prevent leakage of steam. These, however, will not inall cases be necessary. In each abutment-casingis arranged a helicalcompression-spring 29 bearing between the fixed casing and the abutmentand serving to restore said abutment to operative position after thepassage of the piston-wing.

It will be noted on reference to Fig. 1 that the steam-inlet port 20 isarranged inthe rear face of the piston-wing, so that it cannot be closedby the inner edge of the abutment. The forward face of the piston-wingis provided with grooves 30, that extend for almost its entire lengthand merge into the exhaustport 21, so that with the abutments in theposition shown in Fig. 1 the dead steam may freely exhaust from theupper portion of the cylinder and continue to exhaust while the abutmentto the left is being forced out by the piston-wing.

The cylinder-head 13 forms one wall of a steam-chest 32, into which theend of the shaft 14 extends, and in the shaft is an opening or openings33, through which steam may pass from the steam-chest to the hollowshaft and from thence to the cylinder. Mounted on the hollow shaft is acut-off valve in the form of a flanged ring 34, that is under thecontrol of the governor and may be moved lengthwise of the shaft toincrease or decrease the effective area of the openings 33, and thuscontrol the quantity of steam admitted to the engine, in accordance withthe speed. The shaftis provided with a transverse slot through whichextends the flattened portions of a pair of governor-arms 36,approximately of bellcrank form and connected to the shaft by apivot-pin 36. The governor-arms bear against the valve 34 and inoperation tend to move the valve in the direction of the cylinder, andthus cut off the flow of steam through the ports 33. This movement,however, is resisted by a comparatively light compressionspring 37, thatsurrounds the shaft. Against the inner end of the governor-arms bears aring 39, that preferably is provided with a cross-bar 39, extendingthrough thetransverse slot of the shaft in order that a portion of thering or a portion of the arm may at all times be in contact with theinner ends of the governor-arms. The ring 39 is held in position by ahelical compression-spring 40, that tends to move the governor-arms andthe valve-disk to closing position. This spring is in the nature of abalancing-spring and is of less strength than the spring 37. The outerend of the spring 40 bears against a collar or cap 41, that is engagedby a screw 32, disposed in the threaded opening of the outer wall of thesteam-chest, and said screw has a milled head, which may be turned inorder to increase or decrease the stress of the balancing-spring. In thevalve-ring is formed a notch 44, one wall of which is inclined. as shownmore clearly in Fig. 5, and said valve is held from revoluble movementby a pin 45, that extends through a suitable opening formed in an arm ordisk 38,-that is secured to the stationary cylinder, the valve beingthus held from revoluble movement.

In the operation of the engine steam or other fluid pressure passes fromthe chest through the opening or openings 33 to the interior of thehollow shaft and from thence through port 20. The steam-pressure betweenthe rear face of the piston-wing and the opposing abutment 24 causes thepiston to revolve in the direction of the arrow, Fig. 1, while deadsteam escapes from that portion of the cylinder in advance of the wingand passes through the port 21, thence out through the opposite end ofthe hollow shaft. As the piston -wing rotates the abutments aresuccessively moved into their respective casings, and after the passageof the piston-wing said abutments are restored to working position bythe springs 29. During the operation of the engine the governor willcontrol the position of the cut-off valve, and as each port passesbeyond the inclined shoulder of the notch 44 it will be placed incommunication with the steam-chest, and steam will pass therethrough andflow to the hollow shaft and cylinder. As the shaft continues to revolvethe port will pass under the inclined wall of the notch, and the flow ofsteam will be gradually cut off, and the point'of cut-off will depend onthe position of the valve with relation to the shaft. If the engine isrunning at high speed, the valve will be moved nearer the cylinder, andthe cut-ofi' will occur more quickly than if the engine was runningslowly. If the speed decreases, the spring 37 will force the disk 34 inthe direction of the governor-arms, and the weighted ends of the latterwill be moved inwardly. This increases the effective area of the portsand the quantity of steam admitted to the engine. By turning theadjusting-screw the stress of the balancing-spring may be altered, andthis alteration in the sen- IIO sitiveness of the governor will permitany desired increase or decrease of the speed of the engine.

Having thus described the invention, what is claimed is l. Thecombination in a rotary engine, of a cylinder, a revoluble pistondisposed therein and provided with steam inlet and exhaust pas sages, apiston-wing having in its opposite faces ports in communication withsaid passages, the forward face of said wing being curved to form a camand being grooved from the hub to its extreme outer end to permit theescape of steam to the exhaust-port, and pivotallymounted abutmentsmovable outward by engagement with the cam-face of said wing.

2. The combination in a rotary engine, of a cylinder, a piston, a hollowshaft forming a steam-passage, a steam-chest into which the shaftextends, said shaft having an opening through which steam may pass fromthe chest, a valve controlling the area of said opening, and means foradjusting the position of the valve in accordance with the speed of theengine.

3. The combination in a rotary engine, of a cylinder, a piston disposedtherein, a hollow shaft carrying the piston, a steam-chest into whichthe shaft extends, there being an opening in said shaft for the passageof steam from the chest, a valve movable longitudinally of the shaft, aspring tending to prevent movement of the disk to closing position, anda centrifugal governor carried by the shaft and controlling the positionof said disk.

4. The combination in a rotary engine, of a cylinder, a piston disposedtherein, a hollow shaft carrying said piston, a steam-chest into whichthe shaft extends, there being an opening formed in the shaft for thepassage of steam from the chest, a valve mounted on the shaft, a springtending to prevent movement of the disk to closing position, acentrifugal governor carried by the shaft and controlling the positionof the disk, and means for positively limiting movement of said disk.

5. The combination in a rotary engine, of a cylinder, a piston disposedtherein, a hollow shaft carrying said piston, a steam-chest into whichthe shaft extends, an opening being formed in the shaft for the passageof steam from the chest, a valve carried by the shaft, a spring tendingto resist closing movement of said valve, a governor controlling theposition of the valve, a balancing-spring for said governor, and a screwextending through a threaded opening in the wall of the steamchest andserving as a means for adjusting the stress of the balancing-spring.

6. The combination with a revoluble piston, of a hollow ported shaft, asteam-chest into which the shaft extends, and a governor-controlledvalve in the form of a revoluble flanged ring surrounding said shaft andnotched or recessed, the ports of the hollow shaft coming successivelyinto alinement with said notch or recess as the shaft revolves.

7. The combination with a piston, of a hollow ported shaft, asteam-chest into which said shaft extends, a non-revoluble valve-ringmounted on the shaft, and provided with a notch or recess, one wall ofwhich is inclined, governor-arms extending through a transverse slot inthe shaft and bearing against the valve-ring, and a spring-pressed ringbearing on'said governor-arms and tending to move the weighted ends ofthe same inward toward the shaft.

In testimony that I claim the foregoing as my own I have hereto affixedmy signature in the presence of two witnesses.

CHARLES W. CARMAN.

Vitnesses:

JOHN WORMINGTON, I. E. ADAMS.

